Recently pulled the replicator 2 out of storage and it was printing well for a few parts. Then the builds started failing (see https://www.3dhubs.com/talk/thread/failed-printing-replicator-2). I now noticed that the extrusion is really inconsistent, and that the side (blower?) fan is not spinning. Is that the likely culprit? If so, is this likely a case of a MOSFET being blown out? Any advice very welcome.
Most likely its the FET that controls the blower motor, but it could also be the blower motor itself. Best to test the blower motor off the printer, its a 24v fan but will run at 12v DC if you have a small power supply or such to test it.
I’d say it is likely the fan failed. Could be a wire broke. Do test the fan to see if it will actually work.
Also make sure of the voltage. It is likely to be 24v but may be 12.
Also, make sure your slicer is actually set to turn it on!!
Yes, the mosfets are not current rated high enough. I replaced all mine with nds351an mosfets. Watch out for pin out, I think I had to install “dead bug” mode but I cant recall. I cant recall the part# of the original mosfet, but here is a link to the NDS on Digikey (also available at Mouser):